Climbing the Bookshelves, By Shirley Williams

Very few politicians are loved, but Shirley Williams was one. When she joined Roy Jenkins, David Owen and Bill Rodgers to form the SDP in 1981, many Labour people who were happy to say "good riddance" to the others genuinely grieved for her defection. She had a warmth which touched people across the political spectrum. Jenkins and Owen gave the new party political weight, but she gave it humanity and authenticity.

She was such a large part of the early success of the SDP that many, including Owen, wanted her to be leader. But then she ducked the first big challenge, the Warrington by-election, letting Jenkins fight it instead, which effectively conceded him the leadership. Sshe recognises this as "probably the greatest mistake of my life".

Climbing the Bookshelves tries to explain why she missed that critical moment. The book demonstrates both her human qualities and her political failings. The first part, describing her early life, is much the best. The daughter of Vera Brittain, author of Testament of Youth, whose life had been so devastated by the Great War, and her academic husband George Catlin, she grew up in a privileged ambiance of high ideals and public service, a combination of bluestocking and tomboy (perfectly encapsulated in her title).

She writes movingly of her parents, and lyrically of her evacuation to Minnesota during the war – the foundation of her love of America. Back in England she played Cordelia in King Lear at Oxford before throwing herself into the Labour League of Youth and Fabian Society. "That politics was the most exciting of all the exciting things in the world I never doubted".

Yet once she gets into Parliament her account of politics becomes oddly dull, lacking in personal insights. The outward story is the rise and fall of the postwar mixed economy and welfare state inaugurated by the Attlee government, which ran out of vision under Wilson and Callaghan before being dismantled by Thatcher in the Eighties and buried by Blair in the Nineties. "I watched with delight the construction of the welfare state," she writes, "The deep satisfaction of growing up in the cold, austere, wonderful world of the Attlee government was to... be part of that revolution by consent".

But her own career coincided with the disillusion of those utopian hopes – higher living standards, yes, greater freedom and diversity in many spheres, but an abrupt reversal of the steady drive towards a more equal society that her generation took for granted.

"Tony Crosland's vision of equality has been most nearly realised, ironically, in the areas he was least engaged in, race and gender equality". Her hero, perhaps surprisingly, is Jim Callaghan, whose solid decency, "untouched by the awful arrogance that divorces so many top politicians from the real... world", embodies her values. His political life "ran in tandem with the rise and decline of democratic socialism".

So, sadly, did hers. But the real importance of her story lies in the personal – the special difficulty of being a woman in politics. It was not just the slights from men who did not take women seriously, like the Permanent Secretary who refused to speak to a female junior minister, or exclusion from male clubs. Like Mrs Thatcher, she could overcome those obstacles.

Much more serious was the break-up of her marriage, leaving her a single mother with a nine-year old daughter just at the point – 1970 - where her career was beginning to take off. She did not remarry until 1987. So during the whole crisis of Labour and formation of the SDP she was alone, lacking that support only a partner can give.

That was why she ducked Warrington. On her own, she admits that lacked self-confidence, and was afraid of making enemies. "I doubt... that would have mattered so much to me if I had then had the love and support of a spouse like Dick Neustadt". It is harder for a woman. Mrs Thatcher could not have done it without Denis. "Few people write about the partners of political leaders," she concludes, "but they are indispensable'". This is not a great autobiography, but it is – as you would expect – a disarmingly honest one.

John Campbell's 'Pistols at Dawn: two hundred years of political rivalry' is published by Jonathan Cape